Almost a third of the world's forest area is under communal management. In principle, this arrangement could lead to a ``tragedy of the commons'' and therefore more deforestation. But monitoring outsider's deforestation may be easier if the owner is a community rather than an individual. We present a theoretical framework to study these trade-offs and empirically study the effect of communal titling on deforestation in Colombia. The empirical approach uses a differences-in-discontinuities strategy that compares areas just outside and inside a title, before and after titling. Deforestation decreased in communal areas after titling, especially in small communities, consistent with the predictions of the model. This dataverse has the code files for replication, as well as the original raw data (all secondary data either from administrative sources or from previous research done by other teams. All references are in the paper and in the readme files).